PBDB Interval

International Chronostratigraphic Timescale

The interval definitions in this timescale are derived from the following sources:

K. M. Cohen, S.C. Finney, P.L. Gibbard and J.-X. Fan. 2023. The ICS International Chronostratigraphic Chart v2023/09. view
F. M. Gradstein, J. G. Ogg, M. D. Schmitz and G. M. Ogg. 2020. Geologic Time Scale 2020 view
B. D. Webby. 1998. Steps toward a global standard for Ordovician stratigraphy. Newsletters in Stratigraphy 36:1-33 view
W. B. Harland, R. L. Armstrong, A. V. Cox, L. E. Craig, A. G. Smith and D. G. Smith. 1990. A Geologic Time Scale 1989. view
F. F. Steininger, W. A. Berggren, D. V. Kent, R. L. Bernor, S. Sen and J. Agusti. 1996. Circum-Mediterranean Neogene (Miocene and Pliocene) marine-continental chronologic correlations of European mammal units. The Evolution of Western Eurasian Neogene Mammal Faunas (eds. R. L. Bernor, V. Fahlbusch, and H.-W. Mittmann) view

There are 59 timescales which overlap this one. show

Interval boundaries marked with * have been interpolated based on the differences between the ages for international timescale boundaries quoted in the source and the currently accepted ages for those boundaries.

Interval names marked with † are no longer in current use.

This timescale is used in the definition of 126701 collections

Show more time

Show linear time

International Chronostratigraphic Timescale			Ordovician of China			Ordovician of the Baltic				Ordovician of Britain				Ordovician of Ibero-Bohemia
Ordovician	Late Ordovician	Hirnantian	Hirnantian	Xiaoxita †/Shikou	Wufeng †	Harju	Porkuni			Ashgill	Hirnantian			Kosovian				443.8
		Katian	Chientangkiangian				Pirgu				Rawtheyan			Kralodvorian	Bohdalec †			445.2
											Cautleyan							448.9 *
											Pusgillian							449.3 *
			Neichianshanian/Hanjiang								Pusgillian							449.5
							Vormsi			Caradoc	Streffordian	Onnian †						449.6 *
							Vormsi							Berounian				449.7 *
							Nabala	Johvi †										450 *
						Viru	Rakvere											450.6 *
							Rakvere				Cheneyan							451.5 *
							Oandu				Cheneyan							452 *
							Oandu				Burrellian							452.7 *
		Sandbian					Keila	Idavere †										453
							Keila					Actonian †						453.2 *
							Haljala					Actonian †						453.9
												Marshbrookian †	Woolstonian †					454.2 *
												Longvillian †						455.2 *
																Zahorany †/Vinice	Letna †	456.2 *
							Kukruse											456.4 *
											Aurelucian							456.8 *
												Soudleyan †/Harnagian/Costonian						457.4 *
							Uhaku	Aluoja †										457.5 *
															Liben †			458 *
	Middle Ordovician	Darriwilian	Darriwilian	Guniu †/Hulo						Llanvirn	Llandeilian/Llandeilo/Late Llandeilo/Middle Llandeilo/Early Llandeilo/Late Llanvirn							458.4
														Dobrotivian				458.5 *
							Lasnamagi							Dobrotivian				458.9 *
							Lasnamagi							Oretanian				459.7 *
							Aseri											460.4 *
											Abereiddian/Early Llanvirn							461.3 *
															Sarka †			461.7 *
						Oeland	Kunda											462.9 *
								Valaste †/Hunderum										464.3 *
				Hunjiang †	Dawan †/Daobaowan/Ningkuo													466.3 *
							Volkhov		Langevoja †/Vaana/Saka									467.1 *
		Dapingian	Dapingian												Klabava †			467.3
														Arenigian				468
										Arenig	Fennian							468.4 *
							Billingen											469.3 *
	Early Ordovician	Floian	Yiyangian															470
								Latorp †										470.1 *
											Whitlandian							471.1 *
							Hunneberg				Whitlandian							473.7 *
											Moridunian							474.3 *
		Tremadocian	Xinchangian							Tremadoc	Migneintian			Tremadocian				477.7
					Lianghekou †						Migneintian							477.9 *
											Cressagian							480.8 *
							Varangu											481.3 *
							Pakerort											482.2 *
							Pakerort											485 *
																		485.4 *
																		486.3
																		486.5